Effect of Radiotherapy on Activating the Pyroptotic Cell Death Pathway in Breast Cancer Patients: The Role of Serum GSDMD-CT, NLRP3 and IL-18.

BACKGROUND: Breast cancer (BC) is the most common form of cancer among women and the second leading cause of cancer-related death worldwide. Several malignancies can be successfully treated with radiation (RT), although radioresistance is still a major contributor to radiotherapy failure. Ionizing radiation (IR) induces pyroptosis in cancer cells. Pyroptosis is a designed method of death connected to routine immunity and directly related to the body ROS content. Objective for the study: The aim of this work was to investigate the role of serum GSDMD-CT, nucleotide-binding domain and leucine-rich-repeat-containing family pyrin 3 (NLRP3) and IL-18 as predictors of pyroptotic cell death mechanism induced by radiotherapy in breast cancer patients. SUBJECTS AND METHODS: The 70 female participants in this study were divided into two groups: Group (I): 40 breast cancer patients treated with radiotherapy. Group (II): a control group of 30 healthy volunteers with similar ages and sex. Patients with breast cancer received radiation, with a dose of 44 Gray administered over the course of 16 days in five daily fractions of 2.75 Gray each. Two blood samples were taken from breast cancer patients: one before radiotherapy and the other after radiotherapy. While one blood sample was taken from healthy controls. The levels of the circulating pyroptosis biomarkers IL-18, NLRP3, and GSDMD-CT were measured using the ELISA method. RESULTS: Our results showed that, there was a significant increase in serum pyroptosis markers GSDMD-CT, NLRP3 and IL-18 in BC Patients after RT when compared to before radiotherapy. CONCLUSION: Radiotherapy induced pyroptosis in breast cancer patients as a new cell death mechanism. GSDMD-CT, NLRP3 and IL-18 are biomarkers of pyroptosis that significantly increased post irradiation highlighting enhanced ROS and pyroptosis induction.

Vitamin D Receptor in Breast Cancer Tissues and Its Relation to Estrogen Receptor Alpha (ER-α) Gene Expression and Serum 25-hydroxyvitamin D Levels in Egyptian Breast Cancer Patients: A Case-control Study.

INTRODUCTION: This study aimed to explore the role of vitamin D receptor (VDR) in breast cancer tissues and its relation to serum 25-hydroxyvitamin D [25(OH)D] levels and estrogen receptor alpha (ER-α) gene expression in patients with breast cancer. PATIENTS AND METHODS: Cancerous and normal breast tissues from 40 women with breast cancer were analyzed for quantification of VDR levels and ER-α gene expression. The serum levels of 25(OH)D were measured in patients with breast cancer and controls by radioimmunoassay. RESULTS: Patients with breast cancer had serum levels of 25(OH)D significantly lower than normal control subjects. The levels of VDR and ER-α were significantly higher in breast cancer tissues than in normal breast tissues. The serum levels of 25(OH)D were indirectly and significantly correlated with the tissue levels of both VDR and ER-α gene expression. There was a significant direct correlation between the tissue levels of VDR and ER-α gene expression. The serum 25(OH) D levels, tissue VDR levels, and ER-α gene expression levels were inversely and significantly correlated with breast cancer histopathologic grade. Women with serum 25(OH)D levels ≤ 30 nmol/L, tissue levels of VDR > 5 ng/mL, and tissue levels of ER-α gene expression > 17.7 copies had significantly increased risk for breast cancer incidence. CONCLUSION: Women with low serum 25(OH)D levels, high tissue levels of VDR, and ER-α gene expression had increased risk for breast cancer. VDR are upregulated in breast cancer tissues thus it may be used for target therapy especially in hormone-negative breast cancer.

The clinical significance of serum soluble Fas and p53 protein in breast cancer patients: comparison with serum CA 15-3.

Serum sFas and p53 protein have been observed in breast cancer patients, but their clinical usefulness for diagnosis and therapy monitoring has not been clarified. The aim of this study was to compare the clinical utility of serum sFas and p53 protein with that of serum CA 15-3 as the most commonly used breast cancer tumor marker. Serum samples were taken from 35 normal healthy controls and 35 breast cancer patients before surgery, after 2 weeks of surgery and after six cycles of FAC chemotherapy. Serum sFas and p53 protein levels were measured using ELISA kits. Serum CA 15-3 levels were determined using IRMA kit. Mean Serum levels of sFas and CA 15-3 were significantly elevated while p53 protein was significantly declined in breast cancer patients than controls. Serum p53 protein showed the greatest significant area under the ROC curve (84.3%) followed by sFas (80.5%), then CA 15-3 (78%). The sensitivity, specificity and cut-off value for diagnosing breast cancer patients were 84.2%, 82.6% and 2.88 U/ml for p53 protein, 83.3%, 68.2% and 497.3 pg/ml for sFas and 45.8%, 100% and 23 U/ml for CA15-3. Surgical removal of breast resulted in a significant decline in serum sFas level with no effect on serum p53 protein and CA 15-3 levels. Six cycles of chemotherapy resulted in a significant elevation in serum sFas level with no effect on serum p53 protein and CA 15-3 levels. sFas was significantly correlated with tumor grade. It could be concluded that although serum p53 protein is superior to sFas and CA15-3 for diagnosis of breast cancer patients, only sFas is useful for monitoring the response of breast cancer patients to surgery and chemotherapy if the effect of systemic inflammatory reactions is excluded.